“In these kinds of significant colder outbreaks, those numbers can get quite high, in the many thousands.
“While definitely for these western and southern areas you will have noticed a few thunderstorms going off and the occasional lightning strike, it’s not something that is an unusually large number.”
White said a large low-pressure system south of the country was directing cold southwesterly flows from the Southern Ocean, creating unstable conditions.
“We’ve had a decent amount of cold air higher up in the atmosphere come over, and that is really helping drive this shower activity, and it’s what enables these thunderstorms to form.
“That low system is relatively quickly moving, so you’ve noticed places like Invercargill [are] very windy this morning.”
A strong wind watch remains in place for coastal parts of Otago and Southland, including Invercargill, as the blustery conditions continue.
White said people should take care during thunderstorms and avoid being outside where possible.
“There’s always that risk of a lightning strike potentially hitting you. So certainly if you’re outside, try to get inside or in a sheltered place that’s not under a tree.
“It’s a good excuse to kind of have a bit of a hot tea or coffee and just kind of relax inside.”
Looking ahead, more unsettled weather is expected to develop over the weekend as another low-pressure system approaches from the Tasman Sea.
Heavy rain warnings are already in force for parts of Buller and Grey on Saturday, with high confidence of significant rainfall about the ranges.
A lower risk of warning-level rain extends into northern Westland and the ranges of the Tasman District.
In the North Island, there is moderate confidence for warning amounts of rain about Taranaki Maunga and the Tararua Range, with thunderstorms possible in western and northern areas.
Early next week, a large and complex low-pressure system is expected to affect most of the country, bringing further rain, showers and the risk of thunderstorms to northern and central regions.
